Julien Maunoir (1606–1683) (also Julian; Breton: Juluan Maner), was a French-born Jesuit priest known as the "Apostle of Brittany". He was beatified in 1951 by Pope Pius XII and is commemorated by the Roman Catholic Church on 29 January and 2 July.
A classmate of Saints Isaac Jogues and Gabriel Lalemant, he aspired to become a missionary to the peoples of Canada. During his period of priestly formation with the Society of Jesus he was required to learn to preach in the Breton language of the Celtic people of Brittany who reside in the northwestern region of France.
Father Maunoir worked as a missionary to the Breton people for 43 years, and by 1683 had formed 1000 Breton missionaries who carried on the pastoral works that he had begun. Julien Maunoir died in Plévin, Brittany, in 1683 and was buried in the parish church grounds at the insistence of his people.
See also 
- Griffith Jones leader in what was to become the 18th century Welsh revival
- History of Brittany
- Celtic nations
- Canadian Martyrs